/****************************************************************************** * event_channel.h * * Event channels between domains. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to * deal in the Software without restriction, including without limitation the * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or * sell copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. * * Copyright (c) 2003-2004, K A Fraser. */ #ifndef __XEN_PUBLIC_EVENT_CHANNEL_H__ #define __XEN_PUBLIC_EVENT_CHANNEL_H__ #include "xen.h" /* * `incontents 150 evtchn Event Channels * * Event channels are the basic primitive provided by Xen for event * notifications. An event is the Xen equivalent of a hardware * interrupt. They essentially store one bit of information, the event * of interest is signalled by transitioning this bit from 0 to 1. * * Notifications are received by a guest via an upcall from Xen, * indicating when an event arrives (setting the bit). Further * notifications are masked until the bit is cleared again (therefore, * guests must check the value of the bit after re-enabling event * delivery to ensure no missed notifications). * * Event notifications can be masked by setting a flag; this is * equivalent to disabling interrupts and can be used to ensure * atomicity of certain operations in the guest kernel. * * Event channels are represented by the evtchn_* fields in * struct shared_info and struct vcpu_info. */ /* * ` enum neg_errnoval * ` HYPERVISOR_event_channel_op(enum event_channel_op cmd, void *args) * ` * @cmd == EVTCHNOP_* (event-channel operation). * @args == struct evtchn_* Operation-specific extra arguments (NULL if none). */ /* ` enum event_channel_op { // EVTCHNOP_* => struct evtchn_* */ #define EVTCHNOP_bind_interdomain 0 #define EVTCHNOP_bind_virq 1 #define EVTCHNOP_bind_pirq 2 #define EVTCHNOP_close 3 #define EVTCHNOP_send 4 #define EVTCHNOP_status 5 #define EVTCHNOP_alloc_unbound 6 #define EVTCHNOP_bind_ipi 7 #define EVTCHNOP_bind_vcpu 8 #define EVTCHNOP_unmask 9 #define EVTCHNOP_reset 10 #define EVTCHNOP_init_control 11 #define EVTCHNOP_expand_array 12 #define EVTCHNOP_set_priority 13 #ifdef __XEN__ #define EVTCHNOP_reset_cont 14 #endif /* ` } */ typedef uint32_t evtchn_port_t; DEFINE_XEN_GUEST_HANDLE(evtchn_port_t); /* * EVTCHNOP_alloc_unbound: Allocate a port in domain and mark as * accepting interdomain bindings from domain . A fresh port * is allocated in and returned as . * NOTES: * 1. If the caller is unprivileged then must be DOMID_SELF. * 2. may be DOMID_SELF, allowing loopback connections. */ struct evtchn_alloc_unbound { /* IN parameters */ domid_t dom, remote_dom; /* OUT parameters */ evtchn_port_t port; }; typedef struct evtchn_alloc_unbound evtchn_alloc_unbound_t; /* * EVTCHNOP_bind_interdomain: Construct an interdomain event channel between * the calling domain and . must identify * a port that is unbound and marked as accepting bindings from the calling * domain. A fresh port is allocated in the calling domain and returned as * . * * In case the peer domain has already tried to set our event channel * pending, before it was bound, EVTCHNOP_bind_interdomain always sets * the local event channel pending. * * The usual pattern of use, in the guest's upcall (or subsequent * handler) is as follows: (Re-enable the event channel for subsequent * signalling and then) check for the existence of whatever condition * is being waited for by other means, and take whatever action is * needed (if any). * * NOTES: * 1. may be DOMID_SELF, allowing loopback connections. */ struct evtchn_bind_interdomain { /* IN parameters. */ domid_t remote_dom; evtchn_port_t remote_port; /* OUT parameters. */ evtchn_port_t local_port; }; typedef struct evtchn_bind_interdomain evtchn_bind_interdomain_t; /* * EVTCHNOP_bind_virq: Bind a local event channel to VIRQ on specified * vcpu. * NOTES: * 1. Virtual IRQs are classified as per-vcpu or global. See the VIRQ list * in xen.h for the classification of each VIRQ. * 2. Global VIRQs must be allocated on VCPU0 but can subsequently be * re-bound via EVTCHNOP_bind_vcpu. * 3. Per-vcpu VIRQs may be bound to at most one event channel per vcpu. * The allocated event channel is bound to the specified vcpu and the * binding cannot be changed. */ struct evtchn_bind_virq { /* IN parameters. */ uint32_t virq; /* enum virq */ uint32_t vcpu; /* OUT parameters. */ evtchn_port_t port; }; typedef struct evtchn_bind_virq evtchn_bind_virq_t; /* * EVTCHNOP_bind_pirq: Bind a local event channel to a real IRQ (PIRQ ). * NOTES: * 1. A physical IRQ may be bound to at most one event channel per domain. * 2. Only a sufficiently-privileged domain may bind to a physical IRQ. */ struct evtchn_bind_pirq { /* IN parameters. */ uint32_t pirq; #define BIND_PIRQ__WILL_SHARE 1 uint32_t flags; /* BIND_PIRQ__* */ /* OUT parameters. */ evtchn_port_t port; }; typedef struct evtchn_bind_pirq evtchn_bind_pirq_t; /* * EVTCHNOP_bind_ipi: Bind a local event channel to receive events. * NOTES: * 1. The allocated event channel is bound to the specified vcpu. The binding * may not be changed. */ struct evtchn_bind_ipi { uint32_t vcpu; /* OUT parameters. */ evtchn_port_t port; }; typedef struct evtchn_bind_ipi evtchn_bind_ipi_t; /* * EVTCHNOP_close: Close a local event channel . If the channel is * interdomain then the remote end is placed in the unbound state * (EVTCHNSTAT_unbound), awaiting a new connection. */ struct evtchn_close { /* IN parameters. */ evtchn_port_t port; }; typedef struct evtchn_close evtchn_close_t; /* * EVTCHNOP_send: Send an event to the remote end of the channel whose local * endpoint is . */ struct evtchn_send { /* IN parameters. */ evtchn_port_t port; }; typedef struct evtchn_send evtchn_send_t; /* * EVTCHNOP_status: Get the current status of the communication channel which * has an endpoint at . * NOTES: * 1. may be specified as DOMID_SELF. * 2. Only a sufficiently-privileged domain may obtain the status of an event * channel for which is not DOMID_SELF. */ struct evtchn_status { /* IN parameters */ domid_t dom; evtchn_port_t port; /* OUT parameters */ #define EVTCHNSTAT_closed 0 /* Channel is not in use. */ #define EVTCHNSTAT_unbound 1 /* Channel is waiting interdom connection.*/ #define EVTCHNSTAT_interdomain 2 /* Channel is connected to remote domain. */ #define EVTCHNSTAT_pirq 3 /* Channel is bound to a phys IRQ line. */ #define EVTCHNSTAT_virq 4 /* Channel is bound to a virtual IRQ line */ #define EVTCHNSTAT_ipi 5 /* Channel is bound to a virtual IPI line */ uint32_t status; uint32_t vcpu; /* VCPU to which this channel is bound. */ union { struct { domid_t dom; } unbound; /* EVTCHNSTAT_unbound */ struct { domid_t dom; evtchn_port_t port; } interdomain; /* EVTCHNSTAT_interdomain */ uint32_t pirq; /* EVTCHNSTAT_pirq */ uint32_t virq; /* EVTCHNSTAT_virq */ } u; }; typedef struct evtchn_status evtchn_status_t; /* * EVTCHNOP_bind_vcpu: Specify which vcpu a channel should notify when an * event is pending. * NOTES: * 1. IPI-bound channels always notify the vcpu specified at bind time. * This binding cannot be changed. * 2. Per-VCPU VIRQ channels always notify the vcpu specified at bind time. * This binding cannot be changed. * 3. All other channels notify vcpu0 by default. This default is set when * the channel is allocated (a port that is freed and subsequently reused * has its binding reset to vcpu0). */ struct evtchn_bind_vcpu { /* IN parameters. */ evtchn_port_t port; uint32_t vcpu; }; typedef struct evtchn_bind_vcpu evtchn_bind_vcpu_t; /* * EVTCHNOP_unmask: Unmask the specified local event-channel port and deliver * a notification to the appropriate VCPU if an event is pending. */ struct evtchn_unmask { /* IN parameters. */ evtchn_port_t port; }; typedef struct evtchn_unmask evtchn_unmask_t; /* * EVTCHNOP_reset: Close all event channels associated with specified domain. * NOTES: * 1. may be specified as DOMID_SELF. * 2. Only a sufficiently-privileged domain may specify other than DOMID_SELF. * 3. Destroys all control blocks and event array, resets event channel * operations to 2-level ABI if called with == DOMID_SELF and FIFO * ABI was used. Guests should not bind events during EVTCHNOP_reset call * as these events are likely to be lost. */ struct evtchn_reset { /* IN parameters. */ domid_t dom; }; typedef struct evtchn_reset evtchn_reset_t; /* * EVTCHNOP_init_control: initialize the control block for the FIFO ABI. * * Note: any events that are currently pending will not be resent and * will be lost. Guests should call this before binding any event to * avoid losing any events. */ struct evtchn_init_control { /* IN parameters. */ uint64_t control_gfn; uint32_t offset; uint32_t vcpu; /* OUT parameters. */ uint8_t link_bits; uint8_t _pad[7]; }; typedef struct evtchn_init_control evtchn_init_control_t; /* * EVTCHNOP_expand_array: add an additional page to the event array. */ struct evtchn_expand_array { /* IN parameters. */ uint64_t array_gfn; }; typedef struct evtchn_expand_array evtchn_expand_array_t; /* * EVTCHNOP_set_priority: set the priority for an event channel. */ struct evtchn_set_priority { /* IN parameters. */ evtchn_port_t port; uint32_t priority; }; typedef struct evtchn_set_priority evtchn_set_priority_t; /* * ` enum neg_errnoval * ` HYPERVISOR_event_channel_op_compat(struct evtchn_op *op) * ` * Superceded by new event_channel_op() hypercall since 0x00030202. */ struct evtchn_op { uint32_t cmd; /* enum event_channel_op */ union { struct evtchn_alloc_unbound alloc_unbound; struct evtchn_bind_interdomain bind_interdomain; struct evtchn_bind_virq bind_virq; struct evtchn_bind_pirq bind_pirq; struct evtchn_bind_ipi bind_ipi; struct evtchn_close close; struct evtchn_send send; struct evtchn_status status; struct evtchn_bind_vcpu bind_vcpu; struct evtchn_unmask unmask; } u; }; typedef struct evtchn_op evtchn_op_t; DEFINE_XEN_GUEST_HANDLE(evtchn_op_t); /* * 2-level ABI */ #define EVTCHN_2L_NR_CHANNELS (sizeof(xen_ulong_t) * sizeof(xen_ulong_t) * 64) /* * FIFO ABI */ /* Events may have priorities from 0 (highest) to 15 (lowest). */ #define EVTCHN_FIFO_PRIORITY_MAX 0 #define EVTCHN_FIFO_PRIORITY_DEFAULT 7 #define EVTCHN_FIFO_PRIORITY_MIN 15 #define EVTCHN_FIFO_MAX_QUEUES (EVTCHN_FIFO_PRIORITY_MIN + 1) typedef uint32_t event_word_t; #define EVTCHN_FIFO_PENDING 31 #define EVTCHN_FIFO_MASKED 30 #define EVTCHN_FIFO_LINKED 29 #define EVTCHN_FIFO_BUSY 28 #define EVTCHN_FIFO_LINK_BITS 17 #define EVTCHN_FIFO_LINK_MASK ((1 << EVTCHN_FIFO_LINK_BITS) - 1) #define EVTCHN_FIFO_NR_CHANNELS (1 << EVTCHN_FIFO_LINK_BITS) struct evtchn_fifo_control_block { uint32_t ready; uint32_t _rsvd; uint32_t head[EVTCHN_FIFO_MAX_QUEUES]; }; typedef struct evtchn_fifo_control_block evtchn_fifo_control_block_t; #endif /* __XEN_PUBLIC_EVENT_CHANNEL_H__ */ /* * Local variables: * mode: C * c-file-style: "BSD" * c-basic-offset: 4 * tab-width: 4 * indent-tabs-mode: nil * End: */